The present invention relates to an apparatus for maintaining a controlled environment. It is especially concerned with an incubation apparatus for the growth of anaerobes and with a process for transporting such organisms and the transfer of such organisms to and from such an apparatus.
The incubation of anaerobic micro-organisms is currently a difficult and sometimes dangerous task. Most anaerobes require an environment of approximately 37.5.degree. C. temperature and an absence of oxygen for survival. Popular incubators presently in use are gove boxes which contain an atmosphere suitable for the growth of anaerobic organisms. Such incubators are of two basic types: (1) relatively simple plastic glove boxes consisting entirely of flexible plastic walls and containing a variety of equipment assembled for a particular experiment or procedure, and (2) complex metal chambers comprised or rigid materials except for the gloves. The simple devices typically require elaborate set up procedures before each use and are thus unsuitable for prolonged or routine use. The interior of such boxes are of necessity cluttered with equipment such as heaters, fans, connecting wires and the like which hinder maneuverability inside the chamber. The complex chambers are expensive and difficult to operate. They typically are provided with a few rigid viewing ports so that a microscope cannot be used unless it is specially constructed as a part of the chamber wall.
In all of the prior art devices it is difficult to transfer anaerobic specimens into or out of the incubation chamber. To perform this operation some of the more sophisticated prior devices have included an airlock, usually a vacuum airlock chamber, for transferring specimen containers directly from the outside atmosphere into the interior of an incubator. Because vacuum airlock chambers are evacuated of all gas during the transfer of samples, such airlocks have of necessity been constructed of heavy, high strength materials to prevent collapse during evacuation.
Anaerobic micro-organisms will die quickly in an aerobic atmosphere. For this reason airlock pass-throughs are only suitable if the specimen is collected at a location very near to the incubator itself or is transported to the incubator is specimen containers which are self-contained anaerobic units. In institutions such as hospitals where anaerobic specimens are collected at patients' bed sides and other locations remote from a central laboratory, use of anaerobic specimen containers is almost mandatory. Prior incubators have proved to be unsatisfactory in such institutions because currently available anaerobic specimen containers are difficult to operate and often ineffective in sustaining anaerobes during their transport to the incubator.
The vessels commonly used for the transport of anaerobic specimens comprise tanks containing a liquid culture medium. When such vessels are used, specimens must be prepared in a liquid medium and transferred into a tank. The tank is then transported to the incubator and passed through an airlock or its liquid contents are pumped into a storage tank inside the incubator. This arrangement is very inflexible and complicated. It requires extra process steps and equipment and limits the user to liquid culture medium. Special glassware for containing anaerobic cultures is available but is also difficult to use and frequently ineffective.